The miniaturization of the electronics industry has put pressure in the printed circuit board (PCB) industry to create features of fine circuitry. The print and etch processes often used to create PCB's and PCB cores are not precise enough for fine features down to one mil lines and spaces and below. Instead, additive processes using catalytic laminates allows copper (Cu) plating to be performed selectively in photolithographically defined channels and vias using plating resist.
The structure of a multilayer board can be created in many different ways. One way is that no-catalytic cores are made by print and etch to create the circuitry on both faces. The cores are stuck up and laminated followed by drilling and circuitization of the outer layers and the holes.